This research aims to create realistic earthquake scenarios for the expected Main Marmara Fault Earthquake and develop Peak Ground Velocity (PGV) maps using physics-based approaches to protect ~20 million inhabitants in the Istanbul Metropolitan and its surroundings. In this study, a new 3-D dynamic simulation scenario for the expected M≥7.0 earthquake in the Sea of Marmara, incorporates...
Earthquake source parameters are valuable for seismology, including monitoring the Comprehensive Nuclear-Test-Ban Treaty. One needs to determine the hypocentre location, seismic moment, radiated energy, event size, and released stress drop. A stress-strain pattern of the crust is inferred from a statistical analysis of focal mechanisms. It provides information on geometry and kinematics of...
Seismic observation at Syowa Station (69.0°S, 39.6°E; SYO), Antarctica started since 1959 associated with the International Geophysical Year (IGY; 1957-1958) campaign. Since the establishment of the INTELSAT telecommunication link, digital waveform data have been transmitted to the National Institute of Polar Research (NIPR) for the utilization of phase identification more clearly....
The explosive fragmentation of large meteoroids is one of the most significant sources of infrasonic waves. In the absence of atmospheric nuclear tests since 1980, bolide explosions have become key infrasound sources for calibrating and testing the instrument sensitivity of the International Monitoring System (IMS). Moreover, detecting meteoroid explosions with infrasound arrays is crucial for...
The aim of this research is to explore seismic activity in the North Sulawesi Indonesia, which lies within the Pacific Ring of Fire and is highly susceptible to significant earthquakes and tsunamis. The study involved calculating and mapping the distribution of b-values and z-values, as well as identifying the recurrence times of earthquake events. The earthquake data used were sourced from...
In 2024, Cambodia experienced several seismic events, primarily originating from neighboring regions, notably Viet Nam. These earthquakes were felt in various parts of Cambodia, including Ratanakiri province. Notable Earthquakes Near Cambodia in 2024: 28 July 2024: A magnitude 5.1 earthquake occurred near Ratanakiri province. The tremors were felt in the area, marking a significant seismic...
Time-space variations of infrasound source locations for three years, 2019-2021, were studied by using a combination of two local arrays in the Lützow-Holm Bay (LHB), Antarctica. The local arrays deployed at two coastal outcrops detected temporal variations in signal frequency content as well as propagating directions during these years. A large number of infrasound sources were detected with...
Based on the Catalog of earthquakes in Central Asia 1887-2007 (Comprehensive Nuclear-Test-Ban Treaty Organization's National Data Centre of Kazakhstan), a study of seismicity in the Tien Shan was carried out. The epicenters of the strongest earthquakes M≥6.7≥8.4 outline the Tien Shan block parallel to the northern shore of Lake Issyk-Kul. Parallel to the southern shore of Lake Issyk-Kul...
The earthquake catalog is a crucial component in seismic hazard assessment. However, it can be affected by non-natural earthquake sources. Hence, this study aims to differentiate between natural and non-natural earthquakes through machine learning techniques. We propose a convolutional neural network based on spectrograms for waveform classification, applied to the contexte of Madagascar. Our...
Electromagnetic signatures from the Low Yield Nuclear Monitoring PE1 Shot A conducted in October 2023 at the Nevada Nuclear Security Site have been analyzed. The data show signals from the hot, expanding plasma in the Earth's natural magnetic field and from seismo-electric mechanisms. However, the polarization signatures of the prompt signal do not match predictions from a simple "magnetic...
The primary method the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO PrepCom) uses in monitoring for underground nuclear explosions is a seismic network of 50 primary stations and 120 auxiliary stations. Currently the primary network's detection capability has been calculated using theoretical methods. But now that a majority of the network has been...
The rapid deployment of geophones makes them well suited for time limited collects or for events of interest. If the data is going to be analyzed during the deployment time frame, the analyst can ensure high quality data is achieved. In order to better assess the quality of data, we have generated high/low noise models for a variety of deployment types. Having these models as a base line can...
Ice cover monitoring has been recognized as a critical task in environmental studies for hazard mitigation and critical alerts reporting. Current observation methods of changeable ice thickness often fall short in terms of accuracy, completeness and cost efficiency. Distributed acoustic sensing (DAS) uses fiber optic cables as sensitive elements and presents a promising alternative to the...
Accurate seismic event location is essential not only for the Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification but also for national data centers in order to advice national governments. Following the 22nd June 2024 M. 4.4 earthquake locating in Kenya we improve the location of CTBTO at 2.228° S and 39.18444° E with Mb 4.1. The event is also reported by the USGS to be located at...
The Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) operates five seismic monitoring stations in Indonesia. To ensure the traceability of measurement units for these seismometers, in-situ calibration is essential. This study presents a calibration methodology based on the ISO 17025 standard, employing a comparative method where the seismometer to be calibrated is placed side-by-side...
The classification of infrasound signals has important application value in the fields of nuclear test monitoring, earthquake and other natural disaster warning. However, traditional infrasound signals classification methods are difficult to effectively extract the significant features that quantify event differences. To address this issue, this paper proposes an end-to-end infrasound signal...
The DPRK test-site is within regional distances from the Tohoku earthquake fault. No DPRK explosion was conducted during the time when the highest amplitude Tohoku seismic signals travelled over the globe. The conduction of an underground nuclear test near and just after one of the largest earthquakes ever is a well-known evasion scenario. Seismic data from the IMS stations is available for...
During infrasound propagation in the atmosphere, shadow zones can be induced by the temperature and/or wind speed gradients, the ground surface or the source geometry. Although commonly used to simulate the atmospheric infrasound propagation at large scales and three-dimensional domains, acoustic rays method is not able to simulate the propagation where the geometrical approximation is not...
Accurate seismic event location is essential for Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification. This study presents the relocation of a seismic event detected on 22 June 2024, using data from a temporary local network of 20 stations in Nakuru, Kenya, combined with approximately 8 regional stations. The event, initially reported at 2.2896° S, 39.1603° E by IRIS/USGS, varied...
This research explores the application of the YOLOv8 object detection framework for real-time earthquake detection using spectrogram images derived from seismic data. The proposed method is a promising candidate for real-time event detection, with the potential to improve detection accuracy and reduce the risk of human error. By leveraging the strengths of YOLOv8, known for its speed and...
Sudan is classified as an area of moderate seismic activity. The main objective is to study the seismic activity and estimate the morphometric aspect of the North locality. A unified Mw earthquake data for the period between 1906 to 2016 was used to construct the seismicity map. The areal distribution of the earthquake illustrated the concentration of the earthquakes in the eastern part, A Pie...
With the projected increase in world nuclear capacity comes the hurdle of spent nuclear fuel. Pyroprocessing is one method to process irradiated fuel by using high temperatures and electrochemical steps to separate radioactive components of interest. High temperatures, high radiation levels, and equipment confined to a heavily shielded hot cell are a few of the challenges introduced regarding...
In 2012, the National Research Council concluded that earthquake signals cannot effectively mask those produced by explosions. We test that conclusion with multi-channel correlation detectors (correlators) that use records of ground motion (templates) sourced by explosions to detect smaller signals from similar, collocated sources. Our test applies these detectors against thousands of signals...
Albania, situated on the Adriatic microplate boundary, experiences high seismicity. The Gutenberg-Richter relationship, characterized by the a and b values, is crucial for understanding seismicity and forms the foundation for seismic hazard assessment. Using ZMAP7, we analysed seismicity in Albania (18.5–21.5° longitude, 38.0–43.0° latitude) from 2015 to 2024. The declustered seismic catalog,...
We review opportunities afforded by emerging optical submarine cable-based technologies for sensing the marine environment including earthquakes, water waves and explosions. The goal of the submarine fiber sensing Working Group is to enable tsunami early warning based on operational submarine cables. Monitoring changes in water height and temperature in the deep ocean is challenging because...
We performed a comprehensive analysis of the seismic activity in the Valley of Mexico using the records of the nearby seismic stations. We determine the focal mechanisms of earthquakes (M > 2.5) in the Mexico Basin from 2010 to 2024. Events were chosen with a high signal to noise ratio, i.e., raw P and S arrivals clear enough to be distinguished. Focal mechanisms were inverted using the ISOLA...
Seismicity of Africa is moderate by global standards, primarily due to limited recorded earthquakes. However, moment-magnitude Mw larger than 6.0 events frequently occur along poorly understood fault lines, posing significant risks, such as the Mw 6.9 Moroccan earthquake on 8 September 2023. This underscores the urgent need to improve earthquake forecasting on the continent.
Epidemic-Type...
The field of geophysics is seeing rapid development of new technologies, including Distributed Acoustic Sensing (DAS). This innovative technique attracts scientists and researchers for its ability to monitor and analyze geological and structural changes with high spatial resolution over large distances. Unlike traditional methods based on the use of stationary instruments, DAS allows to make...
